冷卻水塔為一特殊之熱交換器，透過兩種流體(水和空氣)的直接接觸，並且使用蒸發和熱對流及熱傳導的方式進行熱交換，其目的是將系統或製程中產生的廢熱，通過循環水吸收後成為熱水並經過冷卻水塔進行熱交換成為冷水，而再一次的進入系統或製程中使用，如此形成一個冷卻水塔之循環。本文首先建立冷卻水塔三維數值模型，並且利用小型風洞實驗量測出填料及擋水器的慣性阻力係數與黏性阻力係數，將此數據帶入商用軟體進行模擬，探討幾種不同的水塔尺寸和外觀設計對冷卻水塔性能的影響，其中有幾個關鍵的數據，可以用來判斷水塔的性能是否能夠達到設計目的，而速度均勻度及風量就是兩個重要的因子。
本文分別以定壓降及定流量之邊界條件來探討不同的進風口高度(A=2500、5980、6580及7180mm)、不同的氣室高度(B=328、1028、2028及3728mm)以及不同導風板的長度(L=0、300、600及1500mm)，透過改變冷卻水塔的幾何尺寸來觀察流場分佈及壓力分佈，本文研究成果可做為未來冷卻水塔之設計參考。

The cooling tower is a special heat exchanger to cool the hot water, through direct contact with the water and air and the use of evaporation and heat convection/conduction. Its purpose is to cool the hot water generated in the system or process, and the hot water becomes cold, and again circulating into the system or process.
In the present study establishes three-dimensional numerical model of the cooling tower and the use of small wind tunnel tests to measure the amount of fill and eliminator the inertial resistance factor and viscous inertial resistance factor. These data are used in the CFD software simulation to explore the performance (velocity uniformity) of the cooling tower.
There are two different boundary conditions used in this study, given pressure drop and mass flow rate. The effects of different air inlet height (A=2500, 5980, 6580, 7180mm), different plenum height (B =328, 1028, 2028 3728mm) and different air inlet guide (L =0, 300, 600, 1500mm) are examined on the flow field and pressure distribution. This thesis would be useful for the future cooling towers design.

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